Tag: statistics

J Relig Health. 2021 Jul 10. doi: 10.1007/s10943-021-01336-0. Online ahead of print.

ABSTRACT

This study was carried out to examine the relationship between international students’ health perceptions and their healthy lifestyle behaviors. This descriptive and relational study was conducted with 216 international students studying at a university in Turkey. Study data were collected using the descriptive information form, the Perception of Health Scale (PHS) and the Health-Promoting Lifestyle Profile II (HPLP-II). Data were evaluated using descriptive statistics and Pearson correlation analysis. It was determined that the health perception and healthy lifestyle behaviors of the international students involved in this study were moderately positive. The study found a weak and positive relationship between PHS and the physical activity, nutrition and stress management subdimensions of HPLP, while a moderate positive relationship was identified between PHS and the spiritual growth and interpersonal relations subdimensions of HPLP. No relationship was observed between PHS and the health responsibility subdimension of HPLP. The fact that students have a positive perception of health reflects positively on their healthy lifestyle behaviors. It is important to disseminate education programs aimed at improving the health perception and healthy lifestyle behaviors of international students within the university.

PMID:34245435 | DOI:10.1007/s10943-021-01336-0

Brain Struct Funct. 2021 Jul 10. doi: 10.1007/s00429-021-02338-0. Online ahead of print.

ABSTRACT

Healthy human aging is associated with a deterioration of visual acuity, retinal thinning, visual field map shrinkage and increasing population receptive field sizes. Here we ask how these changes are related to each other in a cross-sectional sample of fifty healthy adults aged 20-80 years. We hypothesized that age-related loss of macular retinal ganglion cells may lead to decreased visual field map sizes, and both may lead to increased pRF sizes in the cortical central visual field representation. We measured our participants’ perceptual corrected visual acuity using standard ophthalmological letter charts. We then measured their early visual field map (V1, V2 and V3) functional population receptive field (pRF) sizes and structural surface areas using fMRI, and their retinal structure using high-definition optical coherence tomography. With increasing age visual acuity decreased, pRF sizes increased, visual field maps surface areas (but not whole-brain surface areas) decreased, and retinal thickness decreased. Among these measures, only functional pRF sizes predicted perceptual visual acuity, and Bayesian statistics support a null relationship between visual acuity and cortical or retinal structure. However, pRF sizes were in turn predicted by cortical structure only (visual field map surface areas), which were only predicted by retinal structure (thickness). These results suggest that simultaneous disruptions of neural structure and function throughout the early visual system may underlie the deterioration of perceptual visual acuity in healthy aging.

PMID:34245381 | DOI:10.1007/s00429-021-02338-0

Neurol Sci. 2021 Jul 10. doi: 10.1007/s10072-021-05430-9. Online ahead of print.

ABSTRACT

INTRODUCTION: This study aims to evaluate the effect of metabolic syndrome (MetS) and anthropometric indices on carpal tunnel syndrome (CTS).

METHODS: Forty-three healthy controls and 41 CTS patients were enrolled. Complaints of patients were assessed by Boston Questionnaire (BQ). MetS components were investigated. Wrist circumference, wrist depth, wrist width, palm width, and palm length were measured. Routine nerve conduction studies of median and ulnar nerves as well as the “sensitive” comparison tests were performed. Cutaneous silent period (CuSP) was studied by stimulating both second and fifth digital nerves while recording over thenar muscles.

RESULTS: The vast majority of the participants were female and right-handed. CTS was bilateral in 61% of patients. Data of 109 hands were analyzed. MetS was more frequent in CTS patients. BQ scores were not related to MetS. Waist circumference, serum TG, and fasting glucose levels were higher in CTS patients. CTS hands with MetS had lower median CMAP amplitudes and increased sensory thresholds. Sensory thresholds were increased with both median and ulnar nerve stimulations suggesting a wider spread of peripheral nerve excitability changes in MetS presence. CuSPs were recorded from all 109 hands. CuSP latencies and durations were similar between controls and CTS patients. Wrist ratio was the only anthropometric index that was a statistically significant predictor for CTS development.

CONCLUSION: MetS was more prevalent in CTS patients. Some clinical and electrophysiological features (mainly sensory thresholds) may worsen in presence of MetS, but not the wrist ratio.

PMID:34245382 | DOI:10.1007/s10072-021-05430-9

Osteoporos Int. 2021 Jul 10. doi: 10.1007/s00198-021-06046-7. Online ahead of print.

ABSTRACT

Patients with low-energy hip fractures do not follow the obesity paradox as previously reported. In datasets where injury mechanism is not available, the use of age >50 years (as opposed to commonly used >65 years) as a surrogate for a low-energy hip fracture patients may be a more robust inclusion criterion. PURPOSE: In elderly patients with a hip fracture, limited data suggests that obese patients counterintuitively have improved survival compared to normal-weight patients. This “obesity paradox” may be the byproduct of selection bias. We hypothesized that the obesity paradox would not apply to elderly hip fracture patients.

METHODS: The National Surgical Quality Improvement Project dataset identified 71,685 hip fracture patients ≥50 years-of-age with complete body mass index (BMI) data that underwent surgery. Patients were stratified into under and over 75-year-old cohorts (n=18,956 and 52,729, respectively). Within each age group, patients were stratified by BMI class and compared with respect to preoperative characteristics and 30-day mortality. Significant univariate characteristics (p<0.1) were included in multivariate analysis to determine the independent effect of obesity class on 30-day mortality (p<0.05).

RESULTS: Multivariate analysis of <75-year-old patients with class-III obesity were more likely to die within 30-days than similarly aged normal-weight patients (OR 1.91, CI 1.06-3.42, p=0.030). Multivariate analysis of ≥75-year-old overweight (OR 0.69, CI 0.62-0.77, p<0.001), class-I obese (OR 0.62, CI 0.51-0.74, p<0.001), or class-II obese (OR=0.69, CI 0.50-0.95, p=0.022) patients were less likely to die within 30-days when compared to similarly aged normal-weight patients.

CONCLUSIONS: Our data suggest that obesity is a risk factor for mortality in low-energy hip fracture patients, but the appearance of the “obesity paradox” in elderly hip fracture patients results from statistical bias that is only evident upon subgroup analysis.

PMID:34245343 | DOI:10.1007/s00198-021-06046-7

Trop Anim Health Prod. 2021 Jul 10;53(3):395. doi: 10.1007/s11250-021-02824-x.

ABSTRACT

BACKGROUND: Assigning animals to their corresponding breeds through breed informative single-nucleotide polymorphisms (SNPs) is required in many fields. For instance, it is used in the traceability and the authentication of meat and other livestock products. SNPs’ information for several pork breeds are now accessible thanks to the availability of dense SNP chips. These SNP chips cover a large number of molecular markers distributed across the entire genome. To identify the pork breed from a sample of industrial meat, one must analyze a large panel of genetic markers depending on the SNP chip used. The analysis of such large datasets requires intensive work. This leads to the idea of creating less dense chips of breed informative markers based on a reduced number of SNPs. Therefore, the analysis of the data emanating from the genotyping of these reduced chips will require less time and effort.

AIM: The objective of this study is to find the most informative SNPs for the discrimination between four pig breeds, namely Duroc, Landrace, Large White, and Pietrain.

METHOD: The Illumina Porcine 60 k SNP chip was used to genotype SNPs distributed all over the individuals’ genomes. Firstly, we used three different statistical approaches for feature selection: (i) principal component analysis (PCA), (ii) least absolute shrinkage and selection operator (LASSO), and (iii) random forest (RF). These three approaches identified three sets of SNPs; each set corresponds to one approach. Then, we combined the results of the three methods by setting up a final panel containing the SNPs which appear on the three sets altogether.

RESULTS: Separately, each method resulted in a panel with the corresponding most discriminating SNPs. The PCA, the LASSO, and the random forest with Boruta algorithm highlighted 28,816, 50, and 286 SNPs, respectively. The number of SNPs selected by PCA is high compared to Boruta and LASSO because PCA chooses the variables while preserving as much information about the data as possible. The only downside of LASSO regression is that among a group of correlated variables, LASSO tends to select only one variable and ignore the others regardless of their importance. Contrarily to LASSO, the Boruta algorithm considers the interdependence between SNPs and selects informative variables even if they are correlated and have the same effect. The three panels shared 23 SNPs; the distribution of the individuals according to these SNPs showed a grouping of individuals of each breed in well-defined clusters without any overlapping.

CONCLUSIONS: The biological pathways represented by 23 breed informative SNPs resulted by the combination of PCA, LASSO, and Boruta should be explored in further analysis. The results provided by our study are promising for further applications of this method in other livestock animals.

PMID:34245361 | DOI:10.1007/s11250-021-02824-x

World J Surg. 2021 Jul 9. doi: 10.1007/s00268-021-06236-8. Online ahead of print.

ABSTRACT

BACKGROUND: Despite the recently increasing number of elderly patients undergoing liver resection, the impact of advancing age on postoperative infections (PIs) incidence and risk remains unclear. This study aimed to investigate the impact of advancing age on PIs incidence and status.

METHODS: This retrospective study included 744 patients undergoing liver resection without biliary reconstruction or combined resection of other organs. Multivariable analysis with a restricted cubic spline was used to evaluate the impact of advancing age on PIs and to determine its association with PIs risk in patients undergoing open and laparoscopic liver resection (OLR and LLR, respectively).

RESULTS: Multivariable analysis demonstrated that advancing age was significantly associated with increased PIs risk (P = 0.017). The spline curve showed that the odds ratio for PIs sharply increased starting approximately at 65 years of age. Unadjusted restricted cubic splines assessing the subcategories of PIs demonstrated that advancing age was associated with increased risks of organ/space surgical site infection and sepsis (P = 0,064 and 0.048, respectively). Multivariable analysis revealed that LLR was associated with the lower PIs risk compared with OLR (P = 0.025), whereas the lower PIs risk with LLR was not significantly obscured by advancing age (P = 0.29).

CONCLUSIONS: Advancing age was associated with increased risk of PIs, including organ/space surgical site infections and sepsis, after liver resection especially in patients aged ≥ 65 years.

PMID:34244815 | DOI:10.1007/s00268-021-06236-8

Graefes Arch Clin Exp Ophthalmol. 2021 Jul 10. doi: 10.1007/s00417-021-05292-z. Online ahead of print.

ABSTRACT

PURPOSE: Choroidal vascular structures are likely to be affected in diabetic patients. The aim of this study was to conduct a meta-analysis of choroidal vascular structures in diabetic eyes with no diabetic retinopathy (NDR) and healthy control eyes, which was systematically evaluated by various factors involving the measurements.

METHODS: This study identified clinical data from publications in PubMed and web of science until May 2020. Independent retrospective or prospective clinical studies comparing NDR and healthy control eyes regarding choroidal vascular structures were extracted. Five related studies were enrolled, cumulating in a total of 282 diabetic eyes and 511 control eyes examined in this study. Heterogeneity was statistically quantified by I2 statistics, and meta-analysis was performed using a random effects model. This study included 2 different algorisms of binarization determining the ratio of luminal areas in total choroidal areas, both of which were consolidated and called “choroidal vascular ratio.”

RESULTS: Meta-analysis clearly showed that the choroidal vascular ratio was significantly lower in NDR eyes than in healthy control eyes (weighted mean difference = – 2.16; 95%CI: – 3.19 to – 1.13; P < 0.005). Similar results were obtained in sub-analysis based on adjustment of serum HbA1c levels and duration of diabetes.

CONCLUSIONS: The choroidal vascular ratio of NDR eyes was significantly lower than that of healthy control eyes. The ratio might contribute to a better understanding of the pathophysiology involved in the development of diabetic retinopathy, although there was some heterogeneity in primary analysis studies.

PMID:34244824 | DOI:10.1007/s00417-021-05292-z

Mil Med. 2021 Jul 9:usab269. doi: 10.1093/milmed/usab269. Online ahead of print.

ABSTRACT

INTRODUCTION: Anterior cruciate ligament reconstruction (ACLR) ranks among the most common surgeries performed in civilian as well as military orthopedic settings. Regional anesthesia, and the femoral nerve block (FNB) in particular, has demonstrated efficacy in reducing postoperative pain and opioid use after ACLR, however concerns linger about possible impaired functional outcomes. The purpose of the current investigation was to assess International Knee Documentation Committee Subjective Knee Form (IKDC-SKF) scores at 6 to 12 months after ACLR in patients who did (FNB) and did not (NoFNB) receive a perioperative FNB.

MATERIALS AND METHODS: All patients undergoing unilateral ACLR in the study period were reviewed in this institutional process improvement analysis. The primary outcome was prospectively collected IKDC-SKF scores obtained at 6-12 months post-surgery. Demographic and surgical information collected as potential covariates included age, sex, body mass index (BMI), preoperative IKDC-SKF score, use of an FNB, use of another (not femoral nerve) block, American Society of Anesthesiologists (ASA) score, graft type (auto vs. allograft), concomitant meniscus or cartilage procedures, tobacco use, tourniquet time, and primary vs. revision surgery. Assuming a 1:2 ratio of patients who did not vs. did receive FNBs and a clinically meaningful difference of 7 points on the IKDC-SKF, 112 patients were required for 80% power. A regression model averaging approach examined the relationships between covariates and postoperative IKDC-SKF scores.

RESULTS: One hundred nineteen patients met inclusion criteria (FNB 79 and NoFNB 40). The cohorts were significantly different in several factors including BMI, ASA level, graft type, and other peripheral nerve blocks, which were controlled for through regression modeling. Regressions with model averaging examined the relationship between treatment groups and postoperative IKDC-SKF scores, along with other potential predictor variables. Estimated adjusted marginal differences in postoperative IKDC-SKF scores from the best-fitting model revealed a very small 0.66-point mean (P = .86) difference between NoFNB and FNB groups that was not statistically significant. Those who reported tobacco use had a 10.51 point (P = .008) lower mean postoperative IKDC-SKF score than those who did not report tobacco use. Every 1-point increase in the preoperative IKDC-SKF score was associated with a 0.28-point (P = .02) increase in the postsurgical IKDC-SKF score.

CONCLUSIONS: Active tobacco use may negatively impact short-term subjective patient-reported outcomes after ACLR, as reported by the IKDC-SKF. Lower preoperative scores are also associated with significantly lower postoperative IKDC-SKF scores while the use of a FNB was not associated with lower postoperative scores. The negative association between tobacco use and patient-reported functional outcomes after ACLR lends further support to tobacco cessation programs within the military.

PMID:34244804 | DOI:10.1093/milmed/usab269

Mil Med. 2021 Jul 9:usab276. doi: 10.1093/milmed/usab276. Online ahead of print.

ABSTRACT

INTRODUCTION: Multitasking typically requires an individual to simultaneously process cognitive information while performing a motor task. Cognitive motor interference (CMi) is encountered when cognitive challenges negatively impact motor task performance. Military personnel encounter cognitively taxing situations, especially during combat or other tactical performance scenarios, which may lead to injury or motor performance deficits (i.e., shooting inaccuracy, delayed stimulus-response time, and slowed movement speed). The purpose of the current study was to develop four cognitive motor shooting paradigms to determine the effects of cognitive load on shooting performance in healthy Reserve Officers’ Training Corps (ROTC) cadets.

METHODS: Thirty-two healthy collegiate ROTC members (24 male and 8 female; 20.47 ± 1.24 years, 174.95 ± 10.58 cm, and 77.99 ± 13.90 kg) were recruited to complete four simulated shooting tasks with additional “motor” challenge (180° turn, gait, weighted, and unweighted landing) and with and without a “cognitive” decision-making challenge requiring response selection and inhibition to both auditory and visual stimuli, totaling eight multi-task cognitive motor shooting conditions. The current study was approved by the university’s Institutional Review Board. Task initiation (seconds), task completion (seconds), and number of misses were calculated to determine marksmanship efficiency and accuracy. For each task, a multivariate repeated-measures analysis of variance (ANOVA) was conducted for the combined dependent variables. If the overall multivariate repeated-measures ANOVA was significant, follow-up univariate ANOVAs were conducted for each dependent variable. Alpha was set at α = 0.05 for all analyses.

RESULTS: Task initiation increased for the cognitive condition for the 180° turn (4.29 ± 1.22 seconds baseline, 5.09 ± 1.39 seconds cognitive; P < .05), gait (2.76 ± .60 seconds baseline, 3.93 ± .62 seconds cognitive; P < .05), unweighted (1.27 ± .57 seconds baseline, 3.39 ± .63 seconds cognitive; P < .05), and weighted landing (1.46 ± .72 seconds baseline, 3.35 ± .60 seconds cognitive; P < .05). Task completion time increased for the cognitive condition for the 180° turn (3.48 ± 1.53 seconds baseline, 4.85 ± 1.24 seconds cognitive; P < .05), gait (7.84 ± 2.07 seconds baseline, 9.23 ± 1.76 seconds cognitive; P < .05), unweighted (5.98 ± 1.55 seconds baseline, 7.45 ± 1.51 seconds cognitive; P < .05), and weighted landing (6.09 ± 1.42 seconds baseline, 7.25 ± 1.79 seconds cognitive; P < .05). There were no statistically significant differences in the number of misses for any of the tasks between conditions (P > .05).

CONCLUSIONS: The addition of a cognitive load increased both task initiation and task completion times during cognitive motor simulated shooting. Adding cognitive loads to tactical performance tasks can result in CMi and negatively impact tactical performance. Thus, consideration for additional cognitive challenges into training may be warranted to reduce the potential CMi effect on tactical performance.

PMID:34244784 | DOI:10.1093/milmed/usab276

Nucleic Acids Res. 2021 Jul 9:gkab581. doi: 10.1093/nar/gkab581. Online ahead of print.

ABSTRACT

Though single cell RNA sequencing (scRNA-seq) technologies have been well developed, the acquisition of large-scale single cell expression data may still lead to high costs. Single cell expression profile has its inherent sparse properties, which makes it compressible, thus providing opportunities for solutions. Here, by computational simulation as well as experiment of 54 single cells, we propose that expression profiles can be compressed from the dimension of samples by overlapped assigning each cell into plenty of pools. And we prove that expression profiles can be inferred from these pool expression data with overlapped pooling design and compressed sensing strategy. We also show that by combining this approach with plate-based scRNA-seq measurement, it can maintain its superiorities in gene detection sensitivity and individual identity and recover the expression profile with high precision, while saving about half of the library cost. This method can inspire novel conceptions on the measurement, storage or computation improvements for other compressible signals in many biological areas.

PMID:34244789 | DOI:10.1093/nar/gkab581